Duplicating method



Sept 23 1952 R. B. KELLER ET Al. 2,611,313

DUPLICATING METHOD Filed Dec. 1o, 194e ivo 7L 5.21 i /v ATTRNEY.

Patented Sept. 23, 1952 son, Erie, Pa., 4vassignors to Hammermfill Paper Company, SEri'e, Pa., a corporation of Pennsyl- Vania Application December 1o, 1946, serial No. '715,308

Z Claims.

vThe present invention relates to the 4'duplicating art and vmore particularly, fprovides `anovel method for duplicating which method is *ci the type generally referred Vto as spirit duplicating. The present invention also lprovides a novel master sheet for usein spirit duplicating and a Ina-nifold assembly including such master sheet.

In the known processes ef spirit duplicating, special duplicating inks or duplicating carbon paper is 'used to form "a master 'copy vof drawings, or matter written by hand or byv typewriter. Such master copy is formed 'on a blank sheet 4of especially suitable paper vor other material referred to as the master sheet, the ink or `carbon being applied to the master, onlyalong the desired lines to be duplicated, either by hand'or by transfer from the carbon'sheet. The `duplicating ink or carbon issoluble in va duplicating .fluid rsuch las alcohol, water or other suitable solvent with which the copy sheets'or the master sheet is moistened for the :production of multiple copies. In most instances the duplicating'fiuid comprises an alcohol mixture and thus the'delinition spirit duplicating has been adopted.

Since copies are made directly from the master sheet, the data thereon must be in theform of a mirror image. The present invention is adapted for use in the direct process. l

One of the most frequently used systems'for forming a master sheet Will'be described' in order that the later description of the present inventionmay be fully understood. `For the prep'- arati'on ofA a direct process master sheet according to this known process a sheet' of duplicating carbon is placed in a typewriter with the'coated i' 1 side facing outwardly. The master sheet is superimposed upon the coated Vsurface of the itself be moistened a number of times with the proper solvent and placed in contact with the desired number of copy sheets. In either event a portion of the duplicating material in the mirror images en the master sheet will be transferred to each of the successively presented copy sheets.

(Cl. IDI-149:4)

The nature of the duplicating 'in' 'oi carbon is such as 'to be extremely likely to V"smudge "o 'stain the fingers 'oi the 'operator' and soil'or mai' "the ksurface of the master :sheet with 'the result that imperfect reproductions :are formed. Various 'proposals have been made for rapplying'l a protective coating over 'the coating of -duplicating material on the duplicating 'carbon 'sheet tofpreveit such ysmudging. However' such proposals offer only a protective'iilm donot embbdy'me Vnew duplicating process herein disclosed. Furthermore it will be apparent .thatjwh'en .porti-ons of the 'coatings on the duplicating sheet are transferred to the 'master sheet, lasin Ythe typewritin'g `operation f 'describedabo've' the protective 'coating will `rst' be brought 'into Contact with `thefniastr sheet. The Volumeiof'duplcatng material avail- `able'in "each letter or ligure for the production 'of ccpiesfis Vvieduced at least to the 'estentith'at a part ofthe material; transferred tc the master sheet is not aduplicating material.

The present invention provides an entirely uiiferent form of master sheet which 'is itself coated contnuously'onfon'e face theref with 'a suitable duplicating material. A protective coating 'of non-duplicating"material is' placed over the rs't'- mentioned coating. "The protective coating 'is preferablyinsolublein the solvent to. be used .and is such as to be' much more adherent to a backing sheet of paper or the like, when struck-'hy a type bal", than it 1is t0 'the duplicating materia-l `1 the masters-heet. Thus, in the use ofthe present invention, 4a backing'sheet is placed heXtlt the platen of the typewriter and the rnasteisheet is placed thereover with 'the protective coating against the backingsheet. When the typewriter is operated, impact or pressure ci the type bars will transfer the material y'o1' the protectiyecoating to the backing sheet. AWhen the backing' sheet and master 'sheetare' separated,'the duplicating material within the area'of the letters or gures on the ytypebars-will be exposed', It will be apparent that the prepared master V 'sheet Will have an almost continuous coating ofV protective material thereon which coating is broken only in the localized areas where mirror ixnagfes" of the letters voriigures appear.' The master sheet may be brought intol contact with 'moistened copy sheets for the production ofv copiesor, if sodesired, thef'master sheet may itself lie moistened whereby to produce'copies on dry 'sheets Vofcopy paper. i

Certain preferred form .and illustrative-manners of use or the present, iz'uientonv ,wiii The specifically ds'ci'ilitl'- hereinbelow. Such specific descriptions taken in connection with the drawings accompanying and forming a part of this specification will enable those skilled in the art to make use of the present invention in various forms and manners.

In the drawings:

Fig. 1 is a fragmentary sectional view of a master sheet embodying one form of the present invention;

Fig. 2 is a View similar to Fig. 1 but showing a modified form;

Fig. 3 is a diagrammatic view showing the master sheet of Fig. 2 and a backing sheet in assembled position on the platen of a typewriter;V

Fig. 4 is a fragmentary sectional view illustrating in exaggerated diagrammatic form a portion of the master sheet shown in Fig. 2 after impact by the type bars of a typewriting machine;

Fig. 5 is a view similar to Fig. 4 showing the prepared master sheet and the backing sheet after separation; and

Fig. 6 is a fragmentary sectional view of a modified form of the present invention in which the master sheet is shown assembled as in a salesmans order book and the like.

Referring rst to Fig. 1, the master sheet of the present invention comprises a base sheet I of paper, regenerated cellulose, metal foil, glassine, or other exible sheet material normally used in the manufacture of master sheets. The base sheet I has formed thereon a layer or a coating 2 of any suitable duplicating material. The duplicating material may be of the type ordinarily used in the manufacture of duplicating carbon sheets obtainable in the market. Such material may be made from a suitable combination of various waxes, oils and dyestuffs and be of such nature that it is sufiiciently soluble in a duplicating fluid such as an alcohol mixture or other solvent that upon repeatedly moistening the same with the solvent, a portion thereof may be repeatedly transferred to copy sheets in the manner familiar in the art.

In accordance with the present invention, a continuous coating 4, which will be identified herein as a protective layer, is laid upon the exposed surface of the layer 2 of duplicating material. The protective layer is made of a material which has a sufficient affinity for the layer 2 of duplicating material that it will remain united therewith except where it is dislodged as described below. The protective material must have the general characteristics of the waxy compositions normally used in ordinary carbon paper whereby upon impact of a type bar of a typewriting machine. or upon the application of pressure by a stylus or other writing or printing device or apparatus, portions of the protective layer will become temporarily adhesive in nature and stick to a sheet of paper or the like against which it is positioned. The nature of the protective coating used in the present invention, therefore, is preferably such that at the moment of impact or pressure the protective material will have a higher affinity for the backing sheet than it has for the duplicating material within the layer 2. Thus, the portions of the protective layer 4 deposited upon the backing sheet will adhere to the backing sheet when the backing sheet and master sheet are separated and very little, if any, of the duplicating material will be lost.

Specific examples of materials suitable for the protective layer 4 will be set forth hereinbelow. However, in a preliminary way it may be stated that the protective layer preferably 'comprises a 4 suitably flexible, resinous material insoluble in the particular solvent to be used in the duplicating process and insoluble in water. For convenience in manufacture the protective material is preferably soluble or dispersible in a solvent or carrier which will not dissolve the duplicating vmaterial when the protective coating is applied.

In Fig. 2 there is shown a preferred form of master sheet including a base sheet I, layer of duplicating material 2 and protective coating 4 as provided in the form shown in Fig. 1. However, this preferred form of master sheet includes an additional layer 3 of a special parting material interposed between the duplicating material 2 and protective coating 4. Illustratively, the parting layer 3 may comprise a micro-thin coating of a wax or wax-like substance which is too soft or fragile to serve as a protective layer. This parting material is applied as a continuous coating over the duplicating material 2 and the protective layer 4 is then applied as a continuous coating over the parting material 3.

The layer 3 of parting material is particularly advantageous when the duplicating material in layer 2 is of a composition having rather great affinity for the resinous protective layer 4. When the duplicating material is high in wax content, its afnity for the protective layer 4 may be so low that the parting layer may be dispensed with if so desired, but when the duplicating material is of an oily or greasy nature for example, the parting layer 3 is desirable in order to avoid or reduce wasteful transfer of duplicating material to the backing sheet along with the protective layer. A preferred material for the parting layer 3 is carnauba Wax although other similar natural or synthetic waxes may be used. In general, the material or wax selected should be soluble or dispersible in a solvent or carrier which will not dissolve the duplicating material when the parting layer is applied. Furthermore, the solvent or carrier should have a boiling point such as to permit drying at temperatures below the melting point of the duplicating material. Carbon tetrachloride is the preferred solvent for carnauba wax.

In Fig. 3 there is shown a method of assembling the master sheet of the present invention with a backing sheet 5 upon the platen 6 of a'typewriter. The backing sheet 5 is placed in contact with the platen 6 and the master sheet is positioned with the protective coating 4 held against-l the backing sheet 5. The master sheet may be of either of the forms shown in Figs. 1 and 2 but for the purposes of illustration, the Fig. 2 form has been chosen. The parting layer 3 and layer of duplicating material 2 of the master sheet are shown in proper relationship and the base sheet I lies uppermost, the uncoated surface thereof being exposed to type bars 'I of the typewriting machine. It will be understood that the master sheet may be used with or without the usual typewriter ribbon and that if the ribbon is used, a readable copy of the text will be formed on the uncoated or exterior surface of the base sheet I. Impact or pressure of the type bar will be transmitted through the base sheet and the various layers of the material thereon to transfer local areas of the protective coating 4 and parting layer 3 to the upper surface of the backing sheet 5.

In Figs. 4 and 5 there is shown in diagrammatic and exaggerated form the operation of the master sheet of the present invention. The type bars I indent the base sheet I as indicated by the depressions 8. `vLocal areas 9 of the protective layer Will be; depositedv upon.y the. `surfacefoithe backing sheet: 5. The micro-thin parting; layer 3. will be broken in thesesarne localareasreand portions. la thereof,` will' .adhere .to the; portionsi offthey protective layer. the prepared master' sheetA is 'removedairom the. typewriter and separated from vthe backing sheet, as: showniin Fig. 5, the portionsiv andV Iuwill remainfonthe backing sheet and portions. [lofi the' 'duplicating material Will be exposed in an otherwise con.- vtinuous coating vof protective'material.. These exposed areas will be'available 'forfthe forma.- tion off copies in any of the-various manners wellknown in the art. l

In Fig; 6 there isshown. a modi'edassembly in which` a.. master sheet'A incorporating the features ci 'the present invention maybe used. The mastersheetis similar Lto the ones describedin connection with Fig. kl or 2 'and Y may com.- prise a` base sheet l5? havingra continuous'coat'- ing: i6 of duplicating4 materialy thereonv upon which-maybe superimposed, ifV so desired, acontinuousmicro-thin coating ofi parting material l1. A layer orf coating ofv protective' material V|23 is superimposed upon the duplicating'materialy or lupon the Vparting layer ifSthelatter-is provided. The masterl sheet thus formed is superimposed 'With'the coatedside down upon-a backingV sheet Iiibeneathwhich may be'positi'oned any 'desired `number of vinter-leaved pencil carbon sheets `2) kordinary pencil -may be used yfor writing upon the uppersurfaceV of the base sheet' i5; `.Duplicate and triplicate pencil carbon copies Willbe made of'such material and at the same time the protective coatingl I8- and parting,layer llof the master sheet will be locallyv transferred` to `the backing sheet I9. When it is desired to form* a `number of copies ofthe sales sheet, `the master sheet may be removed from thesales book, 'the backing sheet I9 stripped., therefrom vand the master sheet will be availableforfthe production of spirit-duplicated copies. l f

- YSpeci-iic examples will nowv be given ofseveral master sheets embodying the'present invention:

Example 1,-A base sheet of paper f or other flexible sheet material suitable for -useias a master sheet is coated with .a suitable4 duplieating material preferably comprising'a mixture of dye and wax, the dye being of aYDe that is soluble in a duplicating iiuid such as an alcohol mixture or other solvent. The coated, side ofthe base sheet is next coated with a-,carbon tetrachloride solution containing Aeight per centlby Weight cuniarone indeney resin (for example, resins of the types disclosed in U. vS. Patents 11,705,857; 1,770,281; 1,770,283;- 1;922342; 1,990,215; 2,047,246 and 2,092,999) to which is 'added one per cent by weight a plasticizer such as Herculyn made by Athe Hercules Powder Company. The coating thus `applied* is dried at a temperaturebelow the melting point of' the wax-dye composition in the duplicating layenthe boiling point of carbon tetrachloride being suiicient-ly low to permit drying `at temperatures :below the melting point of the various waxes 'ordinarily used' in the Wax-dye duplicating layer. The master sheet thus prepared may be used in ance With- Patent No. 2,263,224).

either of the manners discussed,hereineoritfmay be used in-any-of `the. spirit duplicating: systems in which master sheets prepared byr known vproc-- esses'may be used. The plasticized resin'ofzthe protective layer will be found to sbc. vstable-at room temperature and entirely free fromfany tendency .tosmudge or stain surfaces with which it may comeinto contact.: The resinousilayer,

however, is readily transferable to a backing. sheet upon impact or pressure. incident toY application of printed matter or other indici'a'to the'maste'r sheet for duplication. In. this latter connection the resinous protective material is rendered' temporarily sticky asa result of 'the heatproduced by such impact or pressure and in this condition is-readilyadherent tothe backing sheet.`

Example 2.-A master 'sheet is prepared asi in Example 1 except th'at'after` the duplicatingfmaterial has been coated upon the 'base sheet, a thinl film of a one per cent solution oi'- carnauba wax in carbon tetrachloride is applied' directly to the exposed surface of thewfduplioatingma'- 'teriaLl The quantity of carnaubafwax thus'l ap` plied is very smalland after drying, therewill be letta microethin layeror coatingWh-i'ch `serves asa parting layer as discussed above.A The part'- Ving layer is dried vat a temperaturebelowth'e melting pointsv of the duplicating'materialland the carnauba Wax. A protective coating-*comprising any of the resinous-materialsspeciiied in Example 1 is then placed over the film1 of carnauba wax and dried as described infExamf ple l. The micro-thin` layer of carnaubavwax has very little affinity forv the Wax-dye composition in the duplicating `layer and'v a greater ahnityfor the resinous materialin the pro-tec'- -tive layer. The master sheet ofthe presen-t Yexample maybe used 'in the same mannerfasthat disclosed in Examplefl. When the master-'sheet 'isiwritten upon, selected areas` of the resinous protective layer and the Wax `parting .layer- Wil-1 be deposited upon thebackingfsheet; lVhen the backing sheet is' removed, there Will z'be substantially no duplicating materiall carried along- With :the protective layer- -because of -the loW1-a'f`1inity between the duplicating material` and the ca-r'- nauba Wax.y y y l l Example :li-Abase sheet is-'coatedwith a duplicating materiali'and withy amicro-thin` layer -oicarnauba Wax-asin Example-2.- IA protective 4layer is-next applied Whichc'oinprisc-is''a2r carbon tetrachloride 'solution containing tenfperfcentldy weight a synthetic resin polymerized-from resins in the still `residue from vcolte-Wen "light Y` oil" (prepared, 'for'exanipla in accordancewith USS. Patent No. 2,149,577). Afterr dryingat a tem; peraturevbelou'rthey meltingv point of any vof the waxes present, the master sheet iiiiis'hed.- The vprotective layer in -th-is particular yexample 'is adhesive under pressure oir-"impact and produces resultsV very similar to those obtainedf'withlithe lmaster sheet of Example 2. i l

Example 4.-A-.base sheet having av layerf'of duplicating material and aI'Jarting` layerv as described in-'Exam'ple 2, has applied over thev parting-'layer a protective layer comprising*fourl parts carbon tetrachloride vand one part benzene in which is dissolved eight per cent by' Weight resins 'polymerized fromV pure still residues of the coke-ovenprocess (made, for example, in accord- The protective coating is ldried -at a temperature below the melting point of any ofthe waxespresent. yThe .protective coating is; adhesive underv pressure.A or: im.-

vpact and the mastersheetg according toj the pres,-

ent example, may be used with results substantially identical with those of the master sheet of Example 2. 'Example 5.-A base sheet having a layer of duplicating material and a parting layer as described in Example 2, has applied over the parting layer a protective layer comprising a solution in carbon tetrachloride of seven per cent by weight resins polymerized from indene and methyl indene (a commercial example is Pecco- Var C-l made by Pennsylvania Industrial Chemical Corp.). The protective coating is dried at a temperature below the melting point of any of the waxes present. The protective coating is adhesive under pressure or impact and the master sheet, according to the present example, may be used with results substantially identical with those of the master sheet of Example 2. Example 6.A base sheet having a layer of duplicating material and a parting layer as described in Example 2, has applied over the parting layer a protective layer comprising a solution in carbon tetrachloride of seven per cent by weight a resin polymerized from styrene and its homologues (a commercial example is Piccolastic A-75 made by -Pennsylvania Industrial Chemical Corp.). The protective coating is dried at a temperature below the melting point of any of the waxes present. The protective coating is adhesive under pressure or impact and the master sheet,

according to the present example, may be used with results substantially identical with those of the master sheet of Example 2.

Example 7.-A base sheet having a layer of duplicating material and a parting layer as described in Example 2, has applied over the parting layer a protective layer comprising a carbon tetrachloride solution containing seven per cent by weight resins from the polymerization of beta pinene (a commercial example is Piccolyte S-1l5 made by Pennsylvania Industrial Chemical Corp.) The protective coating is dried at a temperature below the melting point of any of the waxes present. The protective coating is adhesive under pressure or impact and the master sheet, according to the present example, may be used with results substantially identicalwith those of the master sheet of Example 2.

The particular resinous coatings set forth in the above specific examples have been selected because they are readily available and have the characteristics essential to the present invention. It will be noted that in most instances no plasticizers are used, the particular resins having sufficient flexibility without such plasticizers. However, it will be vappreciated that as in the case of the cumarone indene resins a plasticizer may be used in connection with resins otherwise insufficiently flexible. Thus, many resins not mentioned herein will suggest themselves to those skilled in the art and may be adapted to the present invention by the selection of suitable types and quantities of plasticizing materials.

In order to be suitable for use as a protective coating material in the present invention, a particular material must have the following characteristics all of which are possessed by the illustrative materials set forth in the above specific examples. The material must be capable of being coated as a very thin, continuous film, either as a melt or as a solution or dispersion. The material must be non-tacky at normal office temperatures and should not be soluble in or swelled by any of the solvents normally used as duplicator fluid. Alternatively the material may be insoluble in one or more specifcduplicator fluids and the master sheet may be used only with such uids. The film of material also must be insoluble in water in order that the moisture normally present on an operators fingers will not damage the film. The material must be of such nature that the film will become sticky or adhesive to paper or other suitable backing material at the temperature produced by the blow of a typewriter type bar or the pressure of a pencil, stylus or printing press type. In this connection the material will be satisfactory if it has a ring and ball melting point between 70 and 120 C. The fllm of material in the protective layer must not be brittle at normal oflice temperatures and therefore, the material selected should have this characteristic or should lend itself to modification by plasticizers to have such characteristic. As pointed out above, certain materials having all of the characteristics herein set forth will have differing affinity for a particular duplicating material and as a matter of fact, different duplicating materials differ quite widely in respect of tackiness and the like. Accordingly, the microthin parting layer will be found to be of the greatest value in any combination of duplicating material and protective material between which a relatively great affinity exists. The parting layer has been included in each of Examples 2 through 'I without particular regard to the materials in the duplicating and protective layers. While it is preferred to use the parting layer in each of these examples, it will be realized that the layer may be omitted without rendering the master sheet inoperative. When the parting layer is used very little, if any, of the duplicating material will remain adhered to the backing sheet within the areas of transfer of the protective layer thereto. If the parting layer is omitted, varying quantities of duplicating material may be lost in this manner depending upon the ailinity between the particular duplicating material and the particular protective material selected. Thus, in certain instances the number of copies available from a prepared master sheet may be reduced by varying amounts in the event the parting layer is omitted. Therefore, since the parting layer may be rapidly and inexpensively applied in the manufacture of the master sheet blanks, the ability to obtain even a few additional copies -may well offset the slight additional cost incurred when the parting layer is included.

From the above detailed description and specific examples it will be apparent that the master sheet of the present invention accomplishes the objects set forth hereinabove.

l. A method of duplicating which comprises providing a master sheet having a layer of duplicating material soluble in a duplicating fluid, a layer of protective material insoluble in said duplicating fluid overlying said layerof duplicating material, and a micro-thin parting layer of Wax interposed between said layer of duplicating material and said protective layer; transferring localized areas of the protective layer and parting layer of said master sheet to a backing sheet by the application of impact or pressure; separating said backing sheet and said master sheet to expose the duplicating material in said master sheet only within said localized areas; and forming a plurality of duplicate copies from the duplicating material thus exposed.

2. A method for forming a plurality of copies of desired indicia comprising providing a master 9 sheet having a continuous layer of duplicating material on one face thereof, said duplicating material being soluble in a duplicating iiuid. a continuous layer of protective material overlying said duplicating material, and a continuous microthin parting layer of wax interposed between said layer of duplicating material and said layer of protective material, said protective material and said parting layer material being impact or pressure-transferable and said parting layer material being readily separable from said duplicating material; assembling said master sheet with a backing sheet, the protective layer of said master sheet being in face-to-face relation with a surface of said backing sheet; transferring portions o1' said protective layer and said parting layer to said backing sheet in the form of the indicia desired to be duplicated; separating said backing sheet and said master sheet to expose the duplicating material of said master sheet within the areas dened by said indicia; and forming a plurality of duplicate copies of said indicia by bringing the surface of said master sheet having said protective coating thereon into contact successively with a plurality of copy sheets in the presence of duplicating fluid.

RAY BENNETT KELLER. HARROLD BOWMAN DAWSON.

maivmmrzcas'v CITED v,The following references areoiv record in the ille of this patent: Y

Number UNITED STATES OTHER REFERENCES .Printing Inksv by Ellis; VReinhold Pub. Corp.. New York, N. Y. (1940); pages 314-320. Copy in Div. 17. 

1. A METHOD OF DUPLICATING WHICH COMPRISES PROVIDING A MASTER SHEET HAVING A LAYER OF DUPLICATING MATERIAL SOLUBLE IN A DUPLICATING FLUID, A LAYER OF PROTECTIVE MATERIAL INSOLUBLE IN SAID DUPLICATING FLUID OVERLYING SAID LAYER OF DUPLICATING MATERIAL, AND A MICRO-THIN PARTING LAYER OF WAX INTERPOSED BETWEEN SAID LAYER OF DUPLICATING MATERIAL AND SAID PROTECTIVE LAYER; TRANSFERRING LOCALIZED AREAS OF THE PROTECTIVE LAYER AND PARTING LAYER OF SAID MASTER SHEET TO A BACKING SHEET BY THE APPLICATION OF IMPACT OR PRESSURE; SEPARATING SAID BACKING SHEET AND SAID MASTER SHEET TO EXPOSE THE DUPLICATING MATERIAL IN SAID MASTER SHEET ONLY WITHIN SAID LOCALIZED AREAS; AND FORMING A PLURALITY OF DUPLICATE COPIES FROM THE DUPLICATING MATERIAL THUS EXPOSED. 